This study aims to present a philosophical and quantitative perspective of a propulsion system for a large-scale hydrogen-fuelled liquid-hydrogen (LH2) tanker ship. Established methods are used to evaluate the design and performance of an LH2-carrier propulsion system for JAMILA, a ship designed with four cylindrical LH2 tanks bearing a total capacity of ∼280,000 m3 along with cargo and using the boil-off as propulsion and power fuel. Additionally, the ship propulsion system is evaluated based on the ship resistance requirements, and a hydrogen-fuelled combined-cycle gas turbine is modelled to achieve the dual objectives of high efficiency and zero-carbon footprint. The required inputs primarily involve the off-design and degraded performance of the gas-turbine topping cycle, and the proposed power plant operates with a total output power of 50 M.W. The results reveal that the output power allows ship operation at a great speed even with a degraded engine and adverse ambient conditions. Display omitted •H2 fuelled propulsion can be considered as a solution for a marine zero-emission target.•TurboMatch analytical method achieved H2 fuelled propulsion system evaluation.•Azimuthal thruster is suitable for a large-scale liquid-hydrogen tanker ship design.•COGAS can ensure LH2 tanker ships power requirements at variant conditions.•Technical feasibility Hydrogen-fuelled propulsion system can be applicable for the future.